# -*- coding: utf-8 -*-
# @Time    : 2021/9/16 15:33
# @Author  : BrandonGT
# @FileName: city_function.py

def city_country(city, country, population=None):
    """返回格式化输出的内容"""
    if population:
        msg = f"{city}, {country} - population {population}"
    else:
        msg = f"{city}, {country}"
    return msg.title()
